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<article article-type="research-article" dtd-version="1.3" xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xml:lang="ru"><front><journal-meta><journal-id journal-id-type="publisher-id">kaz29</journal-id><journal-title-group><journal-title xml:lang="ru">Вестник Казахстанско-Британского технического университета</journal-title><trans-title-group xml:lang="en"><trans-title>Herald of the Kazakh-British Technical University</trans-title></trans-title-group></journal-title-group><issn pub-type="ppub">1998-6688</issn><issn pub-type="epub">2959-8109</issn><publisher><publisher-name>Казахстанско-Британский Технический Университет</publisher-name></publisher></journal-meta><article-meta><article-id pub-id-type="doi">10.55452/1998-6688-2026-23-1-265-280</article-id><article-id custom-type="elpub" pub-id-type="custom">kaz29-2520</article-id><article-categories><subj-group subj-group-type="heading"><subject>Research Article</subject></subj-group><subj-group subj-group-type="section-heading" xml:lang="ru"><subject>МАТЕМАТИЧЕСКИЕ НАУКИ</subject></subj-group><subj-group subj-group-type="section-heading" xml:lang="en"><subject>MATHEMATICAL SCIENCES</subject></subj-group></article-categories><title-group><article-title>ВАРИАЦИОННЫЙ ПОДХОД К ИДЕНТИФИКАЦИИ ПАРАМЕТРОВ СРЕДЫ ПОСРЕДСТВОМ ОБРАТНОГО АНАЛИЗА РАСПРОСТРАНЕНИЯ АКУСТИЧЕСКИХ ВОЛН</article-title><trans-title-group xml:lang="en"><trans-title>VARIATIONAL APPROACH FOR IDENTIFYING ENVIRONMENTAL PARAMETERS VIA INVERSE ANALYSIS OF ACOUSTIC WAVE PROPAGATION</trans-title></trans-title-group></title-group><contrib-group><contrib contrib-type="author" corresp="yes"><contrib-id contrib-id-type="orcid">https://orcid.org/0000-0002-5828-7820</contrib-id><name-alternatives><name name-style="eastern" xml:lang="ru"><surname>Синица</surname><given-names>А. В.</given-names></name><name name-style="western" xml:lang="en"><surname>Sinitsa</surname><given-names>A. V.,</given-names></name></name-alternatives><bio xml:lang="ru"><p>PhD, ассистент-профессор</p><p>г. Алматы</p></bio><bio xml:lang="en"><p>PhD, Assistant Professor</p><p>Almaty</p></bio><email xlink:type="simple">a.sinitsa@kbtu.kz</email><xref ref-type="aff" rid="aff-1"/></contrib><contrib contrib-type="author" corresp="yes"><contrib-id contrib-id-type="orcid">https://orcid.org/0009-0003-0402-4720</contrib-id><name-alternatives><name name-style="eastern" xml:lang="ru"><surname>Шкорко</surname><given-names>A. K.</given-names></name><name name-style="western" xml:lang="en"><surname>Shkorko</surname><given-names>A. K.</given-names></name></name-alternatives><bio xml:lang="ru"><p>магистр, лектор</p><p>г. Алматы</p></bio><bio xml:lang="en"><p>MSc, Lecturer</p><p>Almaty</p></bio><email xlink:type="simple">a.ukassova@kbtu.kz</email><xref ref-type="aff" rid="aff-1"/></contrib><contrib contrib-type="author" corresp="yes"><contrib-id contrib-id-type="orcid">https://orcid.org/0009-0003-0772-4319</contrib-id><name-alternatives><name name-style="eastern" xml:lang="ru"><surname>Цхай</surname><given-names>Ю. A.</given-names></name><name name-style="western" xml:lang="en"><surname>Tskhay</surname><given-names>Y. A.,</given-names></name></name-alternatives><bio xml:lang="ru"><p>магистр, лектор</p><p>г. Алматы</p></bio><bio xml:lang="en"><p>MSc, Lecturer</p><p>Almaty</p></bio><email xlink:type="simple">y.tskhay@kbtu.kz</email><xref ref-type="aff" rid="aff-1"/></contrib><contrib contrib-type="author" corresp="yes"><contrib-id contrib-id-type="orcid">https://orcid.org/0000-0002-8142-6710</contrib-id><name-alternatives><name name-style="eastern" xml:lang="ru"><surname>Кардук</surname><given-names>А. Р.</given-names></name><name name-style="western" xml:lang="en"><surname>Karduck</surname><given-names>A. P.</given-names></name></name-alternatives><bio xml:lang="ru"><p>PhD, профессор</p><p>г. Фуртванген</p></bio><bio xml:lang="en"><p>PhD, Professor</p><p>Furtwangen</p></bio><email xlink:type="simple">achim.karduck@hs-furtwangen.de</email><xref ref-type="aff" rid="aff-2"/></contrib></contrib-group><aff-alternatives id="aff-1"><aff xml:lang="ru">Казахстанско-Британский технический университет<country>Казахстан</country></aff><aff xml:lang="en">Kazakh-British Technical University<country>Kazakhstan</country></aff></aff-alternatives><aff-alternatives id="aff-2"><aff xml:lang="ru">Университет прикладных наук Фуртвангена<country>Германия</country></aff><aff xml:lang="en">Hochschule Furtwangen University<country>Germany</country></aff></aff-alternatives><pub-date pub-type="collection"><year>2026</year></pub-date><pub-date pub-type="epub"><day>29</day><month>03</month><year>2026</year></pub-date><volume>23</volume><issue>1</issue><fpage>265</fpage><lpage>280</lpage><permissions><copyright-statement>Copyright &amp;#x00A9; Синица А.В., Шкорко A.K., Цхай Ю.A., Кардук А.Р., 2026</copyright-statement><copyright-year>2026</copyright-year><copyright-holder xml:lang="ru">Синица А.В., Шкорко A.K., Цхай Ю.A., Кардук А.Р.</copyright-holder><copyright-holder xml:lang="en">Sinitsa A.V., Shkorko A.K., Tskhay Y.A., Karduck A.P.</copyright-holder><license xml:lang="ru" license-type="creative-commons-attribution" xlink:href="https://creativecommons.org/licenses/by/4.0/" xlink:type="simple"><license-p>Данная работа распространяется под лицензией Creative Commons Attribution 4.0.</license-p></license><license xml:lang="en" license-type="creative-commons-attribution" xlink:href="https://creativecommons.org/licenses/by/4.0/" xlink:type="simple"><license-p>This work is licensed under a Creative Commons Attribution 4.0 License.</license-p></license></permissions><self-uri xlink:href="https://vestnik.kbtu.edu.kz/jour/article/view/2520">https://vestnik.kbtu.edu.kz/jour/article/view/2520</self-uri><abstract><p>В статье представлен численный метод восстановления пространственного распределения скорости звука в неоднородных средах на основе обратного анализа распространения акустических волн. Математическая модель базируется на волновом уравнении второго порядка с переменными коэффициентами. Обратная задача сформулирована как задача оптимизации по минимизации функционала невязки между смоделированными и наблюдаемыми данными давления на границах области. Для эффективного вычисления градиента функционала применяется метод сопряженной (вспомогательной) задачи, выведенный с помощью вариационного исчисления. Численная реализация выполнена с использованием явной конечно-разностной схемы. Вычислительные эксперименты на одномерной модели гетерогенной среды (грунт – металл – грунт) показывают, что предложенный алгоритм позволяет достоверно восстанавливать профиль скорости, особенно в зонах резкого контраста. В работе проведен анализ чувствительности решения и скорости сходимости, показавший, что 500 итераций обеспечивают оптимальный баланс между точностью и вычислительными затратами.</p></abstract><trans-abstract xml:lang="en"><p>This paper presents a numerical method for reconstructing the spatial distribution of sound speed in inhomogeneous media based on the inverse analysis of acoustic wave propagation. The mathematical model relies on the second-order wave equation with variable coefficients. The inverse problem is formulated as an optimization task to minimize the residual functional between simulated and observed pressure data at the domain boundaries. To efficiently calculate the gradient of the functional, an adjoint (auxiliary) problem method is employed, derived via variational calculus. The numerical implementation is performed using an explicit finite-difference scheme. Computational experiments on a one-dimensional model of a heterogeneous medium (soil-metal-soil) demonstrate that the proposed algorithm allows for reliable reconstruction of the velocity profile, particularly in zones of sharp contrast. The study analyzes the sensitivity of the solution and the convergence rate, showing that 500 iterations provide an optimal balance between accuracy and computational cost.</p></trans-abstract><kwd-group xml:lang="ru"><kwd>обратная задача</kwd><kwd>акустическое волновое уравнение</kwd><kwd>метод сопряженных уравнений</kwd><kwd>идентификация параметров</kwd><kwd>градиентный спуск</kwd><kwd>конечно-разностный метод</kwd></kwd-group><kwd-group xml:lang="en"><kwd>inverse problem</kwd><kwd>acoustic wave equation</kwd><kwd>adjoint state method</kwd><kwd>parameter identification</kwd><kwd>gradient descent</kwd><kwd>finite-difference method</kwd></kwd-group></article-meta></front><back><ref-list><title>References</title><ref id="cit1"><label>1</label><citation-alternatives><mixed-citation xml:lang="ru">Sinitsa, A.V., Tskhay, Yu.A., Ukassova, A.K., and Capsoni, A. 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